The quaint store round the corner from Tripoli's Green Square, which was renamed Martyrs Square after rebels took the capital last week, was founded in 1995. Bahbahy drew on 200 works of literature in his personal collection to get started.
"Now I have 12,000 books," he said, gesturing to rows of volumes on subjects including geography, philosophy, politics, science and religion.
His stock also boasts stacks of American thrillers and a banned biography of former US First Lady Nancy Reagan -- whose husband Ronald Reagan ordered the bombing of "terrorist-related" targets in Tripoli as US president in 1986 after Libyan secret forces were blamed for bombing a night club in West Berlin. The attack killed two US servicemen and injured scores more, along with other clients.
The shop, he said, became a safe haven for those with an appetite for culture and a desire to discuss politics freely but "behind closed doors".
Bahbahy said he was never directly threatened by the Kadhafi regime. Thanks to his military past and connections -- coupled with a prudent dose of caution and self-censorship -- intelligence services thought him a supporter of the regime and left him largely alone.
Kadhafi killed the local culture of reading, Bahbahy said, so it was easy to build up his collection as friends and strangers short on education and cash eagerly sold off the books once read by their grandparents when Libya was a monarchy.
Born in the western mountain town of Yefren and educated in military academies in England and the United States, Bahbahy was an army officer when Kadhafi seized power in a bloodless coup in 1969.
-- 'Never in public' --
"We were happy to have the revolution then... but he stole it," he said.
Slowly but surely Kadhafi purged the army of educated officers. Bahbahy's turn came in 1979. After years of dabbling in various business ventures he decided to make a profit out of his childhood passion, too proud to seek help from regime cronies.
"I learned to read the Koran from my grandfather who raised me when I was three. As a teenager, my hobby was to read history books," he said in fluid English.
The regime essentials are readily available on his shelf. There are copies of Kadhafi's infamous Green Book in Arabic, Bengali, English, French, Japanese, Italian, Spanish, and even Hebrew.
"The Green Book was translated into 45 languages -- more than the Koran. Kadhafi thought himself emperor of the whole world so he wanted his theories to reach everyone," Bahbahy said.
Most of his customers, he said, were tourists passing through Tripoli.
Tomes as thick as the Encylopaedia Britannica are piled up on the bookshop's second floor under the watchful gaze of a framed Mona Lisa. They are annual compilations of every oral or written statement made by Kadhafi.
"Now that I am free, I am hungry to read history books that cover all sides," said Bahbahy, a harsh critic of education under Kadhafi, which placed the strongman at the start of history and mapped Libya as the heart of the Arab world and Africa in turn.
"You couldn't say a single word. We would discuss politics in our trusted circle of friends behind closed doors. But never in public and we would never publish.
"Now you can," he said joyfully.
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